ATLANTA - The newly-approved Janssen vaccine began shipping over the weekend, with 3.9 million doses expected to start arriving in US states and territories Tuesday.
It provides protection with just one shot and is easier to store and transport, health officials says since it does not need to be kept in a freezer like the other two vaccines.
The third COVID-19 vaccine to be approved through an Emergency Use Authorization comes as the CDC Director Dr. Rochelle Walensky warns the recent drop in US cases and hospitalizations appears to be stalling, with the US averaging just over 67,000 new infections and about 2,000 new deaths each day.
"We have the ability to stop a potential fourth surge of COVID cases in this country," Dr. Walensky says. "Please stay strong in your conviction. Continue wearing your well-fitting mask and taking the other public health preventions that we know work. Ultimately, vaccination is what will bring us out of this pandemic."
Speed is critical, as the US tries to head off the spread of new, more transmissible variants of the coronavirus.
In clinical trials in the US, the Jansen vaccine was about 72% effective at preventing mild COVID-19 in the US and about 85% effective preventing more severe disease.
Dr. Anthony Fauci says the vaccine was tested on three continents, against new variants in hot spots like Brazil and South Africa, where it performed well against the newer strains.
"So, even though the vaccine itself was not directed specifically against those variants, it did extremely well, when it came to preventing severe critical disease," Dr. Fauci says. "As we've heard many times now, there were no hospitalizations or deaths in any of those studies."
The Janssen vaccine gives vaccine providers more flexibility to launch pop-up or mobile vaccination sites in harder-to-reach communities.
Health officials say the 3 vaccines will be distributed equitably between urban and rural and lower and higher-income communities, and the CDC will be tracking how states are using the vaccine they receive.
Dr. Marcella Nunez-Smith, the COVID-19 Equity Task Force Chair, says some Americans may wish to go with the one-shot vaccine.
There is concern others might defer the Janssen vaccine in order to receive the Pfizer-BioNTech or Moderna vaccines, which were more than 90% effective at preventing milder disease.
Nunez-Smith encouraged Americans not to shop around for a certain vaccine.
"I strongly advise everyone in America to get the first vaccine that is available to you when it is your turn," Dr. Nunez-Smith says. "If people want to opt for one vaccine over another, they may have to wait. Time is of the essence. Getting vaccinated saves lives."
Download the FOX 5 Atlanta app for breaking news and weather alerts.